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Patel A, Bhavanam B, Keenan T, Maruthamuthu V. Integrating shear flow and trypsin treatment to assess cell adhesion strength. Biointerphases 2023; 18:061002. [PMID: 38078793 PMCID: PMC10721339 DOI: 10.1116/6.0003028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/16/2023] [Accepted: 11/14/2023] [Indexed: 12/17/2023] Open
Abstract
Cell adhesion is of fundamental importance in cell and tissue organization and for designing cell-laden constructs for tissue engineering. Prior methods to assess cell adhesion strength for strongly adherent cells using hydrodynamic shear flow either involved the use of specialized flow devices to generate high shear stress or used simpler implementations like larger height parallel plate chambers that enable multihour cell culture but generate low wall shear stress and are, hence, more applicable for weakly adherent cells. Here, we propose a shear flow assay for adhesion strength assessment of strongly adherent cells that employs off-the-shelf parallel plate chambers for shear flow as well as simultaneous trypsin treatment to tune down the adhesion strength of cells. We implement the assay with a strongly adherent cell type and show that wall shear stress in the 0.07-7 Pa range is sufficient to dislodge the cells with simultaneous trypsin treatment. Imaging of cells over a square centimeter area allows cell morphological analysis of hundreds of cells. We show that the cell area of cells that are dislodged, on average, does not monotonically increase with wall shear stress at the higher end of wall shear stresses used and suggest that this can be explained by the likely higher resistance of high circularity cells to trypsin digestion. The adhesion strength assay proposed can be used to assess the adhesion strength of both weakly and strongly adherent cell types and has the potential to be adapted for substrate stiffness-dependent adhesion strength assessment in mechanobiology studies.
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Affiliation(s)
- Antra Patel
- Department of Biological Sciences, Old Dominion University, Norfolk, Virginia 23529
| | - Bhavana Bhavanam
- Department of Biological Sciences, Old Dominion University, Norfolk, Virginia 23529
| | - Trevor Keenan
- Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529
| | - Venkat Maruthamuthu
- Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529
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Patel A, Bhavanam B, Keenan T, Maruthamuthu V. Integrating Shear Flow and Trypsin Treatment to Assess Cell Adhesion Strength. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.26.559598. [PMID: 37808680 PMCID: PMC10557764 DOI: 10.1101/2023.09.26.559598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Cell adhesion is of fundamental importance in cell and tissue organization, and for designing cell-laden constructs for tissue engineering. Prior methods to assess cell adhesion strength for strongly adherent cells using hydrodynamic shear flow either involved the use of specialized flow devices to generate high shear stress or used simpler implementations like larger height parallel plate chambers that enable multi-hour cell culture but generate low shear stress and are hence more applicable for weakly adherent cells. Here, we propose a shear flow assay for adhesion strength assessment of strongly adherent cells that employs off-the-shelf parallel plate chambers for shear flow as well as simultaneous trypsin treatment to tune down the adhesion strength of cells. We implement the assay with a strongly adherent cell type and show that shear stress in the 0.07 to 7 Pa range is sufficient to dislodge the cells with simultaneous trypsin treatment. Imaging of cells over a square centimeter area allows cell morphological analysis of hundreds of cells. We show that the cell area of cells that are dislodged, on average, does not monotonically increase with shear stress at the higher end of shear stresses used and suggest that this can be explained by the likely higher resistance of high circularity cells to trypsin digestion. The adhesion strength assay proposed can be easily adapted by labs to assess the adhesion strength of both weakly and strongly adherent cell types and has the potential to be adapted for substrate stiffness-dependent adhesion strength assessment in mechanobiology studies.
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Affiliation(s)
- Antra Patel
- Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529 USA
| | - Bhavana Bhavanam
- Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529 USA
| | - Trevor Keenan
- Department of Mechanical & Aerospace Engineering, Old Dominion University, Norfolk, VA 23529 USA
| | - Venkat Maruthamuthu
- Department of Mechanical & Aerospace Engineering, Old Dominion University, Norfolk, VA 23529 USA
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3
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Adhesion force measurements on functionalized microbeads: An in-depth comparison of computer controlled micropipette and fluidic force microscopy. J Colloid Interface Sci 2019; 555:245-253. [DOI: 10.1016/j.jcis.2019.07.102] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/29/2019] [Accepted: 07/30/2019] [Indexed: 01/01/2023]
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4
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Tsiaprazi-Stamou A, Monfort IY, Romani AM, Bakalis S, Gkatzionis K. The synergistic effect of enzymatic detergents on biofilm cleaning from different surfaces. BIOFOULING 2019; 35:883-899. [PMID: 31663364 DOI: 10.1080/08927014.2019.1666108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 08/28/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
Biofilm growth is a significant source of contamination in the food industry. Enzymes are considered green countermeasures against biofilm formation in the food industry owing to their biodegradability and low toxicity. In this study, the synergistic effect of enzymes was studied against biofilm cleaning from hard surfaces. A mixed-microbial sample was sourced from a meat packaging line and biofilms were grown under high shear conditions on stainless steel and polyethylene surfaces. A model cleaning-in-place (CIP) parallel-plate flow chamber was used for firstly, the enzymatic cleaning and secondly, a disinfection step. The cleaning effectiveness was evaluated in response to different formulations containing non-foaming commercial surfactants among with amylase, protease and lipase at neutral pH. The formulation combining all three enzymes was the most effective, showing a synergy essential for the deformation of biofilm structure and consequently better disinfection of both material surfaces.
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Affiliation(s)
| | | | - Anna M Romani
- Institute of Aquatic Ecology, University of Girona, Girona, Spain
| | - Serafim Bakalis
- School of Chemical Engineering, University of Birmingham, Birmingham, UK
| | - Konstantinos Gkatzionis
- School of Chemical Engineering, University of Birmingham, Birmingham, UK
- Department of Food Science and Nutrition, School of the Environment, University of the Aegean, Myrina, Lemnos, Greece
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Ungai-Salánki R, Peter B, Gerecsei T, Orgovan N, Horvath R, Szabó B. A practical review on the measurement tools for cellular adhesion force. Adv Colloid Interface Sci 2019; 269:309-333. [PMID: 31128462 DOI: 10.1016/j.cis.2019.05.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/05/2019] [Accepted: 05/06/2019] [Indexed: 01/03/2023]
Abstract
Cell-cell and cell-matrix adhesions are fundamental in all multicellular organisms. They play a key role in cellular growth, differentiation, pattern formation and migration. Cell-cell adhesion is substantial in the immune response, pathogen-host interactions, and tumor development. The success of tissue engineering and stem cell implantations strongly depends on the fine control of live cell adhesion on the surface of natural or biomimetic scaffolds. Therefore, the quantitative and precise measurement of the adhesion strength of living cells is critical, not only in basic research but in modern technologies, too. Several techniques have been developed or are under development to quantify cell adhesion. All of them have their pros and cons, which has to be carefully considered before the experiments and interpretation of the recorded data. Current review provides a guide to choose the appropriate technique to answer a specific biological question or to complete a biomedical test by measuring cell adhesion.
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Papalazarou V, Salmeron-Sanchez M, Machesky LM. Tissue engineering the cancer microenvironment-challenges and opportunities. Biophys Rev 2018; 10:1695-1711. [PMID: 30406572 PMCID: PMC6297082 DOI: 10.1007/s12551-018-0466-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 10/15/2018] [Indexed: 12/25/2022] Open
Abstract
Mechanosensing is increasingly recognised as important for tumour progression. Tumours become stiff and the forces that normally balance in the healthy organism break down and become imbalanced, leading to increases in migration, invasion and metastatic dissemination. Here, we review recent advances in our understanding of how extracellular matrix properties, such as stiffness, viscoelasticity and architecture control cell behaviour. In addition, we discuss how the tumour microenvironment can be modelled in vitro, capturing these mechanical aspects, to better understand and develop therapies against tumour spread. We argue that by gaining a better understanding of the microenvironment and the mechanical forces that govern tumour dynamics, we can make advances in combatting cancer dormancy, recurrence and metastasis.
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Affiliation(s)
- Vassilis Papalazarou
- CRUK Beatson Institute for Cancer Research and Institute of cancer Sciences, University of Glasgow, Garscube Campus, Switchback Road, Bearsden, Glasgow, G61 1BD, UK
- The Centre for the Cellular Microenvironment, University of Glasgow, Glasgow, G12 8QQ, UK
| | | | - Laura M Machesky
- CRUK Beatson Institute for Cancer Research and Institute of cancer Sciences, University of Glasgow, Garscube Campus, Switchback Road, Bearsden, Glasgow, G61 1BD, UK.
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Hu J, Zhou Y, Obayemi JD, Du J, Soboyejo WO. An investigation of the viscoelastic properties and the actin cytoskeletal structure of triple negative breast cancer cells. J Mech Behav Biomed Mater 2018; 86:1-13. [DOI: 10.1016/j.jmbbm.2018.05.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 05/17/2018] [Accepted: 05/28/2018] [Indexed: 12/30/2022]
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Hughes AD, Marsh G, Waugh RE, Foster DG, King MR. Halloysite Nanotube Coatings Suppress Leukocyte Spreading. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:13553-13560. [PMID: 26605493 PMCID: PMC5097672 DOI: 10.1021/acs.langmuir.5b03288] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The nanoscale topography of adhesive surfaces is known to be an important factor governing cellular behavior. Previous work has shown that surface coatings composed of halloysite nanotubes enhance the adhesion, and therefore capture of, rare target cells such as circulating tumor cells. Here we demonstrate a unique feature of these coatings in their ability to reduce the adhesion of leukocytes and prevent leukocyte spreading. Surfaces were prepared with coatings of halloysite nanotubes and functionalized for leukocyte adhesion with E-selectin, and the dilution of nanotube concentration revealed a threshold concentration below which cell spreading became comparable to smooth surfaces. Evaluation of surface roughness characteristics determined that the average distance between discrete surface features correlated with adhesion metrics, with a separation distance of ∼2 μm identified as the critical threshold. Computational modeling of the interaction of leukocytes with halloysite nanotube-coated surfaces of varying concentrations demonstrates that the geometry of the cell surface and adhesive counter-surface produces a significantly diminished effective contact area compared to a leukocyte interacting with a smooth surface.
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Affiliation(s)
- Andrew D. Hughes
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, 14853
| | - Graham Marsh
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, 14627
| | - Richard E. Waugh
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, 14627
| | - David G. Foster
- Department of Chemical Engineering, University of Rochester, Rochester, NY, 14627
| | - Michael R. King
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, 14853
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Hwang G, Klein MI, Koo H. Analysis of the mechanical stability and surface detachment of mature Streptococcus mutans biofilms by applying a range of external shear forces. BIOFOULING 2014; 30:1079-91. [PMID: 25355611 DOI: 10.1080/08927014.2014.969249] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Well-established biofilms formed by Streptococcus mutans via exopolysaccharide matrix synthesis are firmly attached to tooth surfaces. Enhanced understanding of the physical properties of mature biofilms may lead to improved approaches to detaching or disassembling these highly organized and adhesive structures. Here, the mechanical stability of S. mutans biofilms was investigated by determining their ability to withstand measured applications of shear stress using a custom-built device. The data show that the initial biofilm bulk (~ 50% biomass) was removed after exposure to 0.184 and 0.449 N m(-2) for 67 and 115 h old biofilms. However, removal of the remaining biofilm close to the surface was significantly reduced (vs initial bulk removal) even when shear forces were increased 10-fold. Treatment of biofilms with exopolysaccharide-digesting dextranase substantially compromised their mechanical stability and rigidity, resulting in bulk removal at a shear stress as low as 0.027 N m(-2) and > a two-fold reduction in the storage modulus (G'). The data reveal how incremental increases in shear stress cause distinctive patterns of biofilm detachment, while demonstrating that the exopolysaccharide matrix modulates the resistance of biofilms to mechanical clearance.
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Affiliation(s)
- Geelsu Hwang
- a Center for Oral Biology , University of Rochester Medical Center , Rochester , NY , USA
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He Y, Bowen J, Andrews JW, Liu M, Smets J, Zhang Z. Adhesion of perfume-filled microcapsules to model fabric surfaces. J Microencapsul 2014; 31:430-9. [DOI: 10.3109/02652048.2013.871359] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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11
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Nano and Microscale Topographies for the Prevention of Bacterial Surface Fouling. COATINGS 2014. [DOI: 10.3390/coatings4010037] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Boggs T, Carroll R, Tran-Son-Tay R, Yamaguchi H, Al-Mousily F, DeGroff C. Blood Cell Adhesion on a Polymeric Heart Valve Leaflet Processed Using Magnetic Abrasive Finishing. J Med Device 2013. [DOI: 10.1115/1.4025853] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Polymeric heart valves have the potential to improve hemodynamic function without the complications associated with bioprosthetic and mechanical heart valves, but they have exhibited issues that need to be addressed including calcification, hydrolysis, low durability, and the adhesion of blood cells on the valves. These issues are attributed to the valves' material properties and surface conditions in addition to the hemodynamics. To overcome these issues, a new stentless, single-component trileaflet polymeric heart valve with engineered leaflet surface texture was designed, and prototypes were fabricated from a simple polymeric tube. The single-component structure features a trileaflet polymeric valve and conduit that are made of a single tube component to eliminate complications possibly caused by the interaction of multiple materials and components. This paper focuses on the leaflet surface modification and the effects of leaflet surface texture on blood cell adhesion to the leaflet surface. Silicone rubber was chosen as the working material. A magnetic abrasive finishing (MAF) process was used to alter the inner surface of the tubular mold in contact with the silicone leaflets during the curing process. It was hypothesized that the maximum profile height Rz of the mold surface should be smaller than the minimum platelet size of 1 μm to prevent platelets (1–3 μm in diameter) from becoming lodged between the peaks. Cell adhesion studies using human whole blood flushed at low shear stresses over leaflet surfaces with six different textures showed that adhesion of the platelets and red blood cells is greatly influenced by both surface roughness and lay. Leaflets replicated from MAF-produced mold surfaces consisting of short asperities smaller than 1 μm reduced blood cell adhesion and aggregation. Cell adhesion studies also found that either mold or leaflet surface roughness can be used as a measure of cell adhesion.
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Affiliation(s)
| | | | | | - Hitomi Yamaguchi
- e-mail: Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611
| | - Faris Al-Mousily
- Department of Pediatrics, University of Florida, Gainesville, FL 32611
| | - Curt DeGroff
- Congenital Heart Center, University of Florida, Gainesville, FL 32611
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Wagner K, Friedrich S, Stang C, Bley T, Schilling N, Bieda M, Lasagni A, Boschke E. Initial phases of microbial biofilm formation on opaque, innovative anti-adhesive surfaces using a modular microfluidic system. Eng Life Sci 2013. [DOI: 10.1002/elsc.201200035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Katrin Wagner
- Institute of Food Technology and Bioprocess Engineering; Technische Universität Dresden; Dresden Germany
| | - Sandra Friedrich
- Institute of Food Technology and Bioprocess Engineering; Technische Universität Dresden; Dresden Germany
| | - Carolin Stang
- Institute of Food Technology and Bioprocess Engineering; Technische Universität Dresden; Dresden Germany
| | - Thomas Bley
- Institute of Food Technology and Bioprocess Engineering; Technische Universität Dresden; Dresden Germany
| | - Niels Schilling
- Fraunhofer Institute for Material and Beam Technology IWS; Dresden Germany
| | - Matthias Bieda
- Fraunhofer Institute for Material and Beam Technology IWS; Dresden Germany
| | - Andrés Lasagni
- Fraunhofer Institute for Material and Beam Technology IWS; Dresden Germany
| | - Elke Boschke
- Institute of Food Technology and Bioprocess Engineering; Technische Universität Dresden; Dresden Germany
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A practical guide to quantify cell adhesion using single-cell force spectroscopy. Methods 2013; 60:169-78. [DOI: 10.1016/j.ymeth.2013.01.006] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 01/18/2013] [Accepted: 01/24/2013] [Indexed: 01/14/2023] Open
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Shumi W, Kim SH, Lim J, Cho KS, Han H, Park S. Shear stress tolerance of Streptococcus mutans aggregates determined by microfluidic funnel device (μFFD). J Microbiol Methods 2013; 93:85-9. [PMID: 23473926 DOI: 10.1016/j.mimet.2013.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 02/09/2013] [Accepted: 02/11/2013] [Indexed: 11/16/2022]
Abstract
Dental caries are initiated by the attachment of Streptococcus mutans aggregates to the surface of teeth. Bacterial adhesion to the interproximal space, the space between adjacent teeth, has not been investigated due to the lack of devices that mimic the space. Herein, we describe a method for determining the effect of shear stress and sucrose on the attachment of S. mutans aggregates to the interproximal space using microfluidic funnel device (μFFD). Using μFFD, the shear stress tolerance of sucrose-independent and sucrose-dependent S. mutans aggregates (larger than 50 μm in diameter) trapped in the funnel was tested against various flow rates of saliva solution (5 to 50 μl/min). Sucrose-independent aggregates were completely removed from the funnel walls at a low flow rate (10 μl/min) within 7 min., while sucrose-dependent aggregates were removed from the walls only at higher flow rates (25 and 50 μl/min) within several minutes. These results suggest that sucrose-dependent aggregates are more tolerant of shear stress than sucrose-independent aggregates, and are more likely to remain in the region with the smallest shear stress in the teeth.
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Affiliation(s)
- Wahhida Shumi
- Department of Environmental Science and Engineering, Ewha Womans University, Seoul, Republic of Korea
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Significance of nano- and microtopography for cell-surface interactions in orthopaedic implants. J Biomed Biotechnol 2012; 2007:69036. [PMID: 18274618 PMCID: PMC2233875 DOI: 10.1155/2007/69036] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2007] [Accepted: 08/05/2007] [Indexed: 01/12/2023] Open
Abstract
Cell-surface interactions play a crucial role for biomaterial application in orthopaedics. It is evident that not only the chemical composition of solid substances influence cellular adherence, migration, proliferation and differentiation but also the surface topography of a biomaterial. The progressive application of nanostructured surfaces in medicine has gained increasing interest to improve the cytocompatibility and osteointegration of orthopaedic implants. Therefore, the understanding of cell-surface interactions is of major interest for these substances. In this review, we elucidate the principle mechanisms of nano- and microscale cell-surface interactions in vitro for different cell types onto typical orthopaedic biomaterials such as titanium (Ti), cobalt-chrome-molybdenum (CoCrMo) alloys, stainless steel (SS), as well as synthetic polymers (UHMWPE, XLPE, PEEK, PLLA). In addition, effects of nano- and microscaled particles and their significance in orthopaedics were reviewed. The significance for the cytocompatibility of nanobiomaterials is discussed critically.
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Lu J, Yao C, Yang L, Webster TJ. Decreased Platelet Adhesion and Enhanced Endothelial Cell Functions on Nano and Submicron-Rough Titanium Stents. Tissue Eng Part A 2012; 18:1389-98. [DOI: 10.1089/ten.tea.2011.0268] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Jing Lu
- School of Engineering, Brown University, Providence, Rhode Island
| | - Chang Yao
- School of Engineering, Brown University, Providence, Rhode Island
| | - Lei Yang
- School of Engineering, Brown University, Providence, Rhode Island
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Abstract
Platelet deposition, adhesion/aggregation, to the damaged vessel wall or atherosclerotic plaque components has shown to play a major role in hemostasis, thrombosis, and the development of atherosclerosis. Platelet-vessel wall interaction and thrombus formation is driven by blood flow rheology/hemodynamics (changes in local flow conditions), the nature of the flowing blood, and the characteristics of the triggering substrate (lesion type). An extracorporeal perfusion system (the Badimon chamber) was developed to investigate the dynamics of platelet deposition and thrombus formation on: (a) different surfaces (biological and synthetic); (b) under controlled blood flow conditions with varying degrees of stenosis mimicking various vascular conditions (patent and stenotic arteries); and (c) with varying perfusing blood treatments. In the following chapter, we thoroughly describe this experimental approach that has helped to improve the understanding of the pathophysiology of the acute coronary syndromes (Badimon et al., Arteriosclerosis 6:312-320, 1986; Badimon et al., J Lab Clin Med 110:706-718, 1987; Badimon et al., Blood 73:961-967, 1989; Mailhac et al., Circulation 90:988-996, 1994) and is a useful tool for the study and screening of new antithrombotic and platelet-inhibitory compounds (Badimon et al., Thromb Haemost 71:511-516, 1994; Vilahur et al., Circulation 110:1686-1693; Vilahur et al., Thromb Haemost 92:191-200, 2004; Vilahur et al., Cardiovasc Res 61:806-816; Vilahur et al., Thromb Haemost 98:662-669, 2007; Vilahur et al., Thromb Haemost 97:650-657, 2007; Zafar et al., J Thromb Haemost 5:1195-1200, 2007; Lev et al., J Am Coll Cardiol 43:966-971) and for the evaluation of the thrombogenicity associated to synthetic/prosthetic surfaces (Badimon et al., J Biomater Appl 5:27-48, 1990; Badimon et al., ASAIO Trans 33:621-625, 1987) and/or plasma components (cholesterol, glucose levels, etc.) (Badimon et al., Arterioscler Thromb 11:395-402, 1991; Osende et al., J Am Coll Cardiol 38:1307-1312; 2001).
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Affiliation(s)
- Lina Badimon
- Centro de Investigación Cardiovascular, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
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Stem cell-biomaterial interactions for regenerative medicine. Biotechnol Adv 2011; 30:338-51. [PMID: 21740963 DOI: 10.1016/j.biotechadv.2011.06.015] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 05/27/2011] [Accepted: 06/13/2011] [Indexed: 12/11/2022]
Abstract
The synergism of stem cell biology and biomaterial technology promises to have a profound impact on stem-cell-based clinical applications for tissue regeneration. Biomaterials development is rapidly advancing to display properties that, in a precise and physiological fashion, could drive stem-cell fate both in vitro and in vivo. Thus, the design of novel materials is trying to recapitulate the molecular events involved in the production, clearance and interaction of molecules within tissue in pathologic conditions and regeneration of tissue/organs. In this review we will report on the challenges behind translating stem cell biology and biomaterial innovations into novel clinical therapeutic applications for tissue and organ replacements (graphical abstract).
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Yang Y, Kulangara K, Sia J, Wang L, Leong KW. Engineering of a microfluidic cell culture platform embedded with nanoscale features. LAB ON A CHIP 2011; 11:1638-46. [PMID: 21442110 DOI: 10.1039/c0lc00736f] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Cells residing in a microenvironment interact with the extracellular matrix (ECM) and neighboring cells. The ECM built from biomacromolecules often includes nanotopography. Through the ECM, interstitial flows facilitate transport of nutrients and play an important role in tissue maintenance and pathobiology. To create a microenvironment that can incorporate both nanotopography and flow for studies of cell-matrix interactions, we fabricated microfluidic channels endowed with nanopatterns suitable for dynamic culture. Using polymer thin film technology, we developed a versatile stitching technique to generate a large area of nanopatterned surface and a simple microtransfer assembly technique to assemble polydimethylsiloxane-based microfluidics. The cellular study showed that both nanotopography and fluid shear stress played a significant role in adhesion, spreading, and migration of human mesenchymal stem cells. The orientation and deformation of cytoskeleton and nuclei were regulated through the interplay of these two cues. The nanostructured microfluidic platform provides a useful tool to promote the fundamental understanding of cell-matrix interactions and may be used to regulate the fate of stem cells.
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Affiliation(s)
- Yong Yang
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
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Brown A, Burke G, Meenan BJ. Modeling of shear stress experienced by endothelial cells cultured on microstructured polymer substrates in a parallel plate flow chamber. Biotechnol Bioeng 2011; 108:1148-58. [PMID: 21125591 DOI: 10.1002/bit.23022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 10/15/2010] [Accepted: 11/15/2010] [Indexed: 01/20/2023]
Abstract
The application of physical stimuli to cell populations in tissue engineering and regenerative medicine may facilitate significant scientific and clinical advances. However, for the most part, these stimuli are evaluated in isolation, rather than in combination. This study was designed to combine two physical stimuli. The first being a microstructured tissue culture polystyrene substrate, known to produce changes in cell shape and orientation, and the second being laminar shear stress in a parallel plate flow chamber. The combined effects of these stimuli on endothelial cell monolayers cells were evaluated in a parallel plate flow chamber and using a computational fluid dynamics (CFD) model. The topography of the cell monolayers cultured on different microstructured surfaces was determined using confocal laser scanning microscopy (CLSM), and this topographic information was used to construct the CFD model. This research found that while the specific underlying structures were effectively planarized by the cell monolayer, significant differences in cell shape and orientation were observed on the different microstructured surfaces. Cells cultured on grooved substrates aligned in the direction of the grooves and showed higher retention after 1-h LSS conditioning than those cultured on pillars. The modeled shear stress distributions also showed differences. While minor differences in the magnitude of shear stress were noted, aligned cell monolayers experienced significantly lower spatial gradients of shear stress when compared with cells that were not pre-aligned by surface features. The results presented here provide an analysis of how one form of physical stimulus can be moderated by another and also provide a methodology by which the understanding of cell responses to topographic and mechanical stimuli can be further advanced.
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Affiliation(s)
- Alan Brown
- Biomaterials and Tissue Engineering Research Group (BTERG), Nanotechnology and Integrated Bioengineering Centre (NIBEC), University of Ulster, Newtownabbey, UK.
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Atherosclerosis and thrombosis: insights from large animal models. J Biomed Biotechnol 2011; 2011:907575. [PMID: 21274431 PMCID: PMC3022266 DOI: 10.1155/2011/907575] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 12/09/2010] [Indexed: 11/21/2022] Open
Abstract
Atherosclerosis and its thrombotic complications are responsible for remarkably high numbers of deaths. The combination of in vitro, ex vivo, and in vivo experimental approaches has largely contributed to a better understanding of the mechanisms underlying the atherothrombotic process. Indeed, different animal models have been implemented in atherosclerosis and thrombosis research in order to provide new insights into the mechanisms that have already been outlined in isolated cells and protein studies. Yet, although no model completely mimics the human pathology, large animal models have demonstrated better suitability for translation to humans. Indeed, direct translation from mice to humans should be taken with caution because of the well-reported species-related differences. This paper provides an overview of the available atherothrombotic-like animal models, with a particular focus on large animal models of thrombosis and atherosclerosis, and examines their applicability for translational research purposes as well as highlights species-related differences with humans.
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Dan L, Chua CK, Leong KF. Fibroblast response to interstitial flow: A state-of-the-art review. Biotechnol Bioeng 2010; 107:1-10. [DOI: 10.1002/bit.22826] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Biggs MJP, Richards RG, Gadegaard N, McMurray RJ, Affrossman S, Wilkinson CDW, Oreffo ROC, Dalby MJ. Interactions with nanoscale topography: adhesion quantification and signal transduction in cells of osteogenic and multipotent lineage. J Biomed Mater Res A 2009; 91:195-208. [PMID: 18814275 DOI: 10.1002/jbm.a.32196] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Polymeric medical devices widely used in orthopedic surgery play key roles in fracture fixation and orthopedic implant design. Topographical modification and surface micro-roughness of these devices regulate cellular adhesion, a process fundamental in the initiation of osteoinduction and osteogenesis. Advances in fabrication techniques have evolved the field of surface modification; in particular, nanotechnology has allowed the development of nanoscale substrates for the investigation into cell-nanofeature interactions. In this study human osteoblasts (HOBs) were cultured on ordered nanoscale pits and random nano "craters" and "islands". Adhesion subtypes were quantified by immunofluorescent microscopy and cell-substrate interactions investigated via immuno-scanning electron microscopy. To investigate the effects of these substrates on cellular function 1.7 k microarray analysis was used to establish gene profiles of enriched STRO-1+ progenitor cell populations cultured on these nanotopographies. Nanotopographies affected the formation of adhesions on experimental substrates. Adhesion formation was prominent on planar control substrates and reduced on nanocrater and nanoisland topographies; nanopits, however, were shown to inhibit directly the formation of large adhesions. STRO-1+ progenitor cells cultured on experimental substrates revealed significant changes in genetic expression. This study implicates nanotopographical modification as a significant modulator of osteoblast adhesion and cellular function in mesenchymal populations.
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Affiliation(s)
- Manus J P Biggs
- Centre for Cell Engineering, Institute of Biomedical and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G128QQ, United Kingdom.
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Choi CH, Heydarkhan-Hagvall S, Wu BM, Dunn JCY, Beygui RE, Kim CJ. Cell growth as a sheet on three-dimensional sharp-tip nanostructures. J Biomed Mater Res A 2009; 89:804-17. [PMID: 18523950 DOI: 10.1002/jbm.a.32101] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cells in vivo encounter with and react to the extracellular matrix materials on a nanometer scale. Recent advances in nanofabrication technologies allowing the precise control of a nanostructure's pattern, periodicity, shape, and height have enabled a systematic study of cell interactions with three-dimensional nanotopographies. In this report, we examined the behavior of human foreskin fibroblasts on well-ordered dense arrays (post and grate patterns with a 230-nm pitch) of sharp-tip nanostructures with varying three-dimensionalities (from 50 to 600 nm in structural height) over time-until a cell sheet was formed. Although cells started out smaller and proliferated slower on tall nanostructures (both posts and grates) than on smooth surfaces, they became confluent to form a sheet in 3 weeks. On grate patterns, significant cell elongation in alignment with the underlying pattern was observed and maintained over time. On tall nanostructures, cells grew while raised on sharp tips, resulting in a weak total adherence to the solid surface. A sheet of cells was easily peeled off from such surfaces, suggesting that nanoscale topographies can be used as the basis for cell-sheet tissue engineering.
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Affiliation(s)
- Chang-Hwan Choi
- Mechanical and Aerospace Engineering Department, University of California, Los Angeles, 90095, USA.
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27
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Zhang M, Horbett TA. Tetraglyme coatings reduce fibrinogen and von Willebrand factor adsorption and platelet adhesion under both static and flow conditions. J Biomed Mater Res A 2009; 89:791-803. [PMID: 18496865 DOI: 10.1002/jbm.a.32085] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Previous studies have showed that radio-frequency plasma deposited tetraglyme coatings greatly reduced fibrinogen adsorption (Gamma(Fg)) from highly diluted plasmas (0.1 and 1%) and subsequent platelet adhesion under static conditions. In this study, the protein resistant properties of tetraglyme were re-examined with high-concentration plasma, and subsequent platelet adhesion was measured under both static and flow conditions. The resistance of tetraglyme to vWf adsorption (Gamma(vWf)) and the role of vWf in platelet adhesion under flow were also investigated. Gamma(Fg) and Gamma(vWf) were measured with (125)I radiolabeled proteins. Flow studies were done at shear rates of 50 or 500 s(-1) by passing a platelet/red cell suspension through a GlycoTech flow chamber. When adsorbed from a series of increasing plasma concentrations, the adsorption of both proteins to tetraglyme increased steadily, and did not show a peak at intermediate dilutions, i.e., there was no Vroman effect. When plasma concentration was less than 10%, the tetraglyme surface was highly nonfouling, exhibiting ultralow Gamma(Fg) (less than 5 ng/cm(2)) and extremely low platelet adhesion under both static and flow conditions. However, when the adsorption was done from 100% plasma, Gamma(Fg) was much higher ( approximately 85 ng/cm(2)), indicating that tetraglyme surface may not be sufficiently protein-resistant in the physiological environment. To correlate platelet adhesion under flow with Gamma(Fg) and Gamma(vWf), a series of tetraglyme surfaces varying in ether content and protein adsorption was created by varying deposition power. On these surfaces, platelet adhesion at low shear rate depended only on the amount of Gamma(Fg), but under high shear, both Gamma(Fg) and Gamma(vWf) affected platelet adhesion. In particular, it was found that Gamma(vWf) must be reduced to less than 0.4 ng/cm(2) to achieve ultra low platelet adhesion under high shear.
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Affiliation(s)
- Min Zhang
- Department of Bioengineering, University of Washington, Seattle, 98195, USA
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Slater JH, Frey W. Nanopatterning of fibronectin and the influence of integrin clustering on endothelial cell spreading and proliferation. J Biomed Mater Res A 2008; 87:176-95. [PMID: 18085648 DOI: 10.1002/jbm.a.31725] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Investigating stages of maturation of cellular adhesions to the extracellular matrix from the initial binding events to the formation of small focal complexes has been challenging because of the difficulty in fabricating the necessary nanopatterned substrates with controlled biochemical functionality. We present the fabrication and characterization of surfaces presenting fibronectin nanopatterns of controlled size and pitch that provide well-defined cellular adhesion sites against a nonadhesive polyethylene glycol background. The nanopatterned surfaces allow us to control the number of fibronectin proteins within each adhesion site from 9 to 250, thereby limiting the number of integrins involved in each cell-substrate adhesion. We demonstrate the presence of fibronectin on the nanoislands, while no protein was observed on the passivated background. We show that the cell adheres to the nanopatterns with adhesions that are much smaller and more evenly distributed than on a glass control. The nanopattern influences cellular proliferation only at longer times, but influences spreading at both early and later times, indicating adhesion size and adhesion density play a role in controlling cell adhesion and signaling. However, the overall density of fibronectin on all patterns is far lower than on homogeneously coated control surfaces, showing that the local density of adhesion ligands, not the average density, is the important parameter for cell proliferation and spreading.
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Affiliation(s)
- John H Slater
- Department of Biomedical Engineering and Center for Nano and Molecular Science and Technology, University of Texas at Austin, 1 University Station C0800, Austin, Texas 78712, USA
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Kim SM, Lee SH, Suh KY. Cell research with physically modified microfluidic channels: a review. LAB ON A CHIP 2008; 8:1015-23. [PMID: 18584072 DOI: 10.1039/b800835c] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
An overview of the use of physically modified microfluidic channels towards cell research is presented. The physical modification can be realized either by combining embedded physical micro/nanostructures or a topographically patterned substrate at the micro- or nanoscale inside a channel. After a brief description of the background and the importance of the physically modified microfluidic system, various fabrication methods are described based on the materials and geometries of physical structures and channels. Of many operational principles for microfluidics (electrical, magnetic, optical, mechanical, and so on), this review primarily focuses on mechanical operation principles aided by structural modification of the channels. The mechanical forces are classified into (i) hydrodynamic, (ii) gravitational, (iii) capillary, (iv) wetting, and (v) adhesion forces. Throughout this review, we will specify examples where necessary and provide trends and future directions in the field.
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Affiliation(s)
- Sun Min Kim
- Department of Mechanical Engineering, Inha University, 253 Young Hyun-dong, Nam-gu, Incheon 402-751, Republic of Korea
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Minelli C, Kikuta A, Tsud N, Ball MD, Yamamoto A. A micro-fluidic study of whole blood behaviour on PMMA topographical nanostructures. J Nanobiotechnology 2008; 6:3. [PMID: 18284677 PMCID: PMC2279145 DOI: 10.1186/1477-3155-6-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Accepted: 02/19/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Polymers are attractive materials for both biomedical engineering and cardiovascular applications. Although nano-topography has been found to influence cell behaviour, no established method exists to understand and evaluate the effects of nano-topography on polymer-blood interaction. RESULTS We optimized a micro-fluidic set-up to study the interaction of whole blood with nano-structured polymer surfaces under flow conditions. Micro-fluidic chips were coated with polymethylmethacrylate films and structured by polymer demixing. Surface feature size varied from 40 nm to 400 nm and feature height from 5 nm to 50 nm. Whole blood flow rate through the micro-fluidic channels, platelet adhesion and von Willebrand factor and fibrinogen adsorption onto the structured polymer films were investigated. Whole blood flow rate through the micro-fluidic channels was found to decrease with increasing average surface feature size. Adhesion and spreading of platelets from whole blood and von Willebrand factor adsorption from platelet poor plasma were enhanced on the structured surfaces with larger feature, while fibrinogen adsorption followed the opposite trend. CONCLUSION We investigated whole blood behaviour and plasma protein adsorption on nano-structured polymer materials under flow conditions using a micro-fluidic set-up. We speculate that surface nano-topography of polymer films influences primarily plasma protein adsorption, which results in the control of platelet adhesion and thrombus formation.
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Affiliation(s)
- Caterina Minelli
- International Centre for Young Scientists, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
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31
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Kwon KW, Choi SS, Lee SH, Kim B, Lee SN, Park MC, Kim P, Hwang SY, Suh KY. Label-free, microfluidic separation and enrichment of human breast cancer cells by adhesion difference. LAB ON A CHIP 2007; 7:1461-8. [PMID: 17960272 DOI: 10.1039/b710054j] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
A label-free microfluidic method for separation and enrichment of human breast cancer cells is presented using cell adhesion as a physical marker. To maximize the adhesion difference between normal epithelial and cancer cells, flat or nanostructured polymer surfaces (400 nm pillars, 400 nm perpendicular, or 400 nm parallel lines) were constructed on the bottom of polydimethylsiloxane (PDMS) microfluidic channels in a parallel fashion using a UV-assisted capillary moulding technique. The adhesion of human breast epithelial cells (MCF10A) and cancer cells (MCF7) on each channel was independently measured based on detachment assays where the adherent cells were counted with increasing flow rate after a pre-culture for a period of time (e.g., one, two, and four hours). It was found that MCF10A cells showed higher adhesion than MCF7 cells regardless of culture time and surface nanotopography at all flow rates, resulting in label-free separation and enrichment of cancer cells. For the cell types used in our study, an optimum separation was found for 2 hours pre-culture on the 400 nm perpendicular line pattern followed by flow-induced detachment at a flow rate of 200 microl min(-1). The fraction of MCF7 cells was increased from 0.36 +/- 0.04 to 0.83 +/- 0.04 under these optimized conditions.
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Affiliation(s)
- Keon Woo Kwon
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Korea
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32
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Roach P, Eglin D, Rohde K, Perry CC. Modern biomaterials: a review - bulk properties and implications of surface modifications. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2007; 18:1263-77. [PMID: 17443395 DOI: 10.1007/s10856-006-0064-3] [Citation(s) in RCA: 216] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Accepted: 05/08/2006] [Indexed: 05/14/2023]
Abstract
This review concerns the importance of length and time on physicochemical interactions between living tissue and biomaterials that occur on implantation. The review provides information on material host interactions, materials for medical applications and cell surface interactions, and then details the extent of knowledge concerning the role(s) that surface chemistry and topography play during the first stage of implant integration, namely protein adsorption. The key points are illustrated by data from model in vitro studies. Host implant interactions begin nanoseconds after first contact and from then on are in a state of flux due to protein adsorption, cell adhesion and physical and chemical alteration of the implanted material. The many questions concerning the conformational form and control of bound proteins and how this may impact on cell adhesion in the first instance and later on cell signalling and implant integration can be answered by systematic investigations using model materials. Only then we will be in a more informed position to design new materials for use in the body.
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Affiliation(s)
- Paul Roach
- Division of Chemistry, Interdisciplinary Biomedical Research Centre, School of Biomedical and Natural Sciences, Nottingham Trent University, Clifton, Nottingham, UK
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Gross PG, Kartalov EP, Scherer A, Weiner LP. Applications of microfluidics for neuronal studies. J Neurol Sci 2007; 252:135-43. [PMID: 17207502 DOI: 10.1016/j.jns.2006.11.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 11/01/2006] [Accepted: 11/07/2006] [Indexed: 10/23/2022]
Abstract
Microfabrication processes have changed the technology used in consumer goods, and have now advanced into applications in biology. Microfluidic platforms are microfabricated tools that are gaining popularity for studies of molecular and cellular biology. These platforms can allow precise control of the environment surrounding individual cells and they have been used to study physiologic and pharmacologic responses at the single-cell level. This article reviews microfluidic technology with emphasis on advances that could apply to the study of the nervous system, including architecture for isolation of axons, integrated electrophysiology, patterned physical and chemical substrate cues, and devices for the precisely controlled delivery of possible therapeutic agents such as trophic factors and drugs. The potential of these chips for the study of neurological diseases is also discussed.
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Affiliation(s)
- Pamela G Gross
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
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34
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Funk RHW, Monsees TK. Effects of electromagnetic fields on cells: physiological and therapeutical approaches and molecular mechanisms of interaction. A review. Cells Tissues Organs 2006; 182:59-78. [PMID: 16804297 DOI: 10.1159/000093061] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/26/2006] [Indexed: 01/22/2023] Open
Abstract
This review concentrates on findings described in the recent literature on the response of cells and tissues to electromagnetic fields (EMF). Models of the causal interaction between different forms of EMF and ions or biomolecules of the cell will be presented together with our own results in cell surface recognition. Naturally occurring electric fields are not only important for cell-surface interactions but are also pivotal for the normal development of the organism and its physiological functions. A further goal of this review is to bridge the gap between recent cell biological studies (which, indeed, show new data of EMF actions) and aspects of EMF-based therapy, e.g., in wounds and bone fractures.
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Affiliation(s)
- Richard H W Funk
- Department of Anatomy, University of Technology, Dresden, Germany.
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35
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Vogel V, Sheetz M. Local force and geometry sensing regulate cell functions. Nat Rev Mol Cell Biol 2006; 7:265-75. [PMID: 16607289 DOI: 10.1038/nrm1890] [Citation(s) in RCA: 1576] [Impact Index Per Article: 87.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The shapes of eukaryotic cells and ultimately the organisms that they form are defined by cycles of mechanosensing, mechanotransduction and mechanoresponse. Local sensing of force or geometry is transduced into biochemical signals that result in cell responses even for complex mechanical parameters such as substrate rigidity and cell-level form. These responses regulate cell growth, differentiation, shape changes and cell death. Recent tissue scaffolds that have been engineered at the micro- and nanoscale level now enable better dissection of the mechanosensing, transduction and response mechanisms.
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Affiliation(s)
- Viola Vogel
- Laboratory for Biologically Oriented Materials, Department of Materials, Swiss Federal Institute of Technology (ETH), Zurich, Wolfgang-Pauli-Strasse 10, ETH Hönggerberg, HCI F443, CH-8093 Zürich, Switzerland.
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Bogner E, Dominizi K, Hagl P, Bertagnolli E, Wirth M, Gabor F, Brezna W, Wanzenboeck HD. Bridging the gap--biocompatibility of microelectronic materials. Acta Biomater 2006; 2:229-37. [PMID: 16701882 DOI: 10.1016/j.actbio.2005.10.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Revised: 10/14/2005] [Accepted: 10/19/2005] [Indexed: 11/22/2022]
Abstract
There is an increasing interest in cell-based microelectronic biosensors for high-throughput screening of new products from the biotech pipeline. This requires fundamental knowledge of the biocompatibility of the materials used as the growing support for the cells. Using monolayer-forming Caco-2 cells of human origin, the biocompatibility of silicon wafers coated with various metals, dielectrics and semiconductors was assessed. Besides microscopic inspection, proliferation of cells indicating viability as well as brush border enzyme activity indicating differentiation of adherent growing cells were chosen as parameters to estimate biocompatibility. The type of wafer used for deposition of the coating initially influences the biocompatibility of the final product. Whereas p-doped silicon was fully biocompatible, n-doped silicon reduced the proliferation of cells. Among the different coatings, Al and Ti even increased the cell growth as compared to glass. Culturing the cells for 6 days on coated wafers demonstrated that the differentiation of adhering cells on Ti- and ZrO2-coated wafers was comparable to glass, whereas coatings with Si3N4, Au, Al, and ITO reduced differentiation to 15-35%. In the cases of Au and Si3N4 this effect equilibrated with prolonged culturing. These results demonstrate the importance of a careful selection of the materials used for the production of cell-based biosensors.
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Affiliation(s)
- E Bogner
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Althanstrasse 14, UZA 2, 1090 Vienna, Austria.
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Eisenbarth E, Velten D, Müller M, Thull R, Breme J. Nanostructured niobium oxide coatings influence osteoblast adhesion. J Biomed Mater Res A 2006; 79:166-75. [PMID: 16788971 DOI: 10.1002/jbm.a.30823] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The interaction of osteoblasts was correlated to the roughness of nanosized surface structures of Nb(2)O(5) coatings on polished CP titanium grade 2. Nb(2)O(5) sol-gel coatings were selected as a model surface to study the interaction of osteoblasts with nanosized surface structures. The surface roughness was quantified by determination of the average surface finish (Ra number) by means of atomic force microscopy. Surface topographies with Ra = 7, 15, and 40 nm were adjusted by means of the annealing process parameters (time and temperature) within a sol-gel coating procedure. The observed osteoblast migration was fastest on smooth surfaces with Ra = 7 nm. The adhesion strength, spreading area, and collagen-I synthesis showed the best results on an intermediate roughness of Ra = 15 nm. The surface roughness of Ra = 40 nm was rather peaked and reduced the speed of cell reactions belonging to the adhesion process.
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Affiliation(s)
- E Eisenbarth
- Biomechanic, Hamburg University of Technology TUHH, Hamburg, Germany.
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Monsees TK, Barth K, Tippelt S, Heidel K, Gorbunov A, Pompe W, Funk RHW. Effects of Different Titanium Alloys and Nanosize Surface Patterning on Adhesion, Differentiation, and Orientation of Osteoblast-Like Cells. Cells Tissues Organs 2005; 180:81-95. [PMID: 16113537 DOI: 10.1159/000086749] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2005] [Indexed: 11/19/2022] Open
Abstract
To test nanosize surface patterning for application as implant material, a suitable titanium composition has to be found first. Therefore we investigated the effect of surface chemistry on attachment and differentiation of osteoblast-like cells on pure titanium prepared by pulsed laser deposition (TiPLD) and different Ti alloys (Ti6Al4V, TiNb30 and TiNb13Zr13). Early attachment (30 min) and alkaline phosphatase (ALP) activity (day 5) was found to be fastest and highest, respectively, in cells grown on TiPLD and Ti6Al4V. Osteoblasts seeded on TiPLD produced most osteopontin (day 10), whereas expression of this extracellular matrix protein was an order of magnitude lower on the TiNb30 surface. In contrast, expression of the corresponding receptor, CD44, was not influenced by surface chemistry. Thus, TiPLD was used for further experiments to explore the influence of surface nanostructures on osteoblast adhesion, differentiation and orientation. By laser-induced oxidation, we produced patterns of parallel Ti oxide lines with different widths (0.2-10 microm) and distances (2-20 and 1,000 microm), but a common height of only 12 nm. These structures did not influence ALP activity (days 5-9), but had a positive effect on cell alignment. Two days after plating, the majority of the focal contacts were placed on the oxide lines. The portion of larger focal adhesions bridging two lines was inversely related to the line distance (2-20 microm). In contrast, the portion of aligned cells did not depend on the line distance. On average, 43% of the cells orientated parallel towards the lines, whereas 34% orientated vertically. In the control pattern (1,000 microm line distance), cell distribution was completely at random. Because a significant surplus of the cells preferred a parallel alignment, the nanosize difference in height between Ti surface and oxide lines may be sufficient to orientate the cells by contact guiding. However, gradients in electrostatic potential and surface charge density at the Ti/Ti oxide interface may additionally influence focal contact formation and cell guidance.
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Affiliation(s)
- Thomas K Monsees
- Department of Anatomy, University of Technology, Dresden, Germany.
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Monsees TK, Funk RHW. Wirkung von Oberflächenladungen und elektro-magnetischen Feldern auf Zellen. ACTA ACUST UNITED AC 2005. [DOI: 10.1515/biomat.2005.6.2.67] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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